Egg
and nest specimens are catalogued separately from traditional specimens
(skins, skeletons, fluids). The egg and nest collection contains approximately
14,000 items, including over 12,800 egg sets, 220 nests, and 900 egg-nest
combinations. The size of this collection ranks it as one of the largest
such collections in North America. Eggs of nest parasites (e.g., cowbirds)
are present in 120 sets, and 150 egg sets or nests are associated with
catalogued bird specimens.
The earliest egg specimen was collected in 1843, with growth concentrated from the late 1800s to early-mid 1900s. Eggs in this collection represent all major orders of bird, and range in size from the tiny eggs of hummingbirds (0.2 grams) to the gigantic eggs of the extinct elephant bird (9 kilograms). Geographic representation is greatest for western North America, but there also are significant holdings from Europe, Asia, Africa, and most other continents.
Over 80% of the specimens are accompanied by data slips from the original collector. In addition to information on collecting locality, date, clutch size, incubation, and identification, these slips contain data on nest composition and nest placement. MVZ curatorial staff have nearly finished capturing these data for addition to the database.
Although
the egg and nest collection receives less use by researchers than traditional
specimens, it still provides an important resource for studies of geographic
variation, breeding phenology, and contaminants. Perhaps the most significant
use of the MVZ collection was in the study of pesticide effects (DDT
and DDE) on eggshell formation. Researchers measured eggs collected
before and after the introduction of these pesticides, in the MVZ and
other collections, and showed conclusively that the pesticides were
responsible for widespread eggshell thinning and reproductive failure
in birds - resulting in population declines of Brown Pelicans, Peregrine
Falcons, and other species.
